BMW Repair: air conditioning/heating, unreachable areas, smoke bomb

Question
I've owned the car 523se around 6 months, and recently i've noticed a musky smell coming from the heaters, only when hot the aircon is fine, i've changed the pollen filters and also had a smoke bomb type cannister run through with aircon con on circulate (as recommended due to bacterior build up) however the musky smell from the heaters is still present, is there any advice you can give me pls, much appreciated  Steve  

Answer
Hi there,

It would seem that you have done almost all you can to try to eliminate the odour. The only thing would be to remove as much of the venting as possible and spray an anti-bacterial  to ensure that all areas are reached by the anti-bacterial agent.
Try attaching a thin hose/pipe to the end of an aerosol can and penetrating deeper into the vents direct, you might end up with a bit of fluid pooling in the pipework but this will clear out and (with the system on re-cycle) help to clear any unreachable areas as the fluid atomises.

Sorry I can't be of more help.

If you do succeed, try switching the a/c off a few minutes before you switch the car itself off, as this will help the system to clear out any residual water and prevent the build up of bacteria.


Regards

Rob